purnell



(No Model.) 2 sneeuw-sheen 2.' J. J. PURNELL.

GAS MOTUR ENGINE.

No. 408,13?. Patented July 30, 1889.

UNiTnD STATES FnTnNT Orricn.

JOHN J. PURNELL, OF LAMBETH, COUNTY OF SURREY, ENGLAND.

GAS-MOTOR ENGINE.

SPECIFICATION forming part of Letters Patent No. 408,137', dated July 30, 1889.

Application tiled May 15, 1889. Serial No. 310,860. (No model.) Patented in England July 12, 1888, No. 10,165.

To aZfZ whom, it may concern.:

Be it known that I, JOHN JAMES PURNELL, a citizen of England,residing at-Atlas lVorks, lVebber Street, Lambeth, in the county of Surrey, Iilngland, have invented a new and Improved Gas-Motor Engine, (for which I obtained Letters Patent in Great Britain, dated July 12, 1888, No. lO,lG5,) of which the following is a specification. A

My invention relates to a gas-motor engine of simple and inexpensive construction, as I describe, referring to the accompanying drawings.

Figure l is a front elevation with the valvecase shown in section, and Fig. 2 is a side elevation ofa gas-motor engine according to my invention.

On a hollow base A stands a vertical cylinder B, which is open at the top and is surrounded, as usual, with a water-casing. The cylinder has a trunk-piston C, connected to the crank on the fly-wheel shaft D, which is mounted in bearings carried overhead in brackets E, extending` up from and in one piece with the cylinder B. In the cavity of the base A is a valve-case containing two valves F and G, both opening upward to a space H in free communication with the interior of the cylinder B. The one valve F is kept closed by a spring f and is opened to discharge exhaust by an arm K of a rocking shaft L, which has another arm M, connected to a crank N, or it might be an eccentric or cam on a counter-shaft driven by gearing O from the shaft D at half the speed. The other valve G is self-acting,ope1ii1ig to admit air by the pipe g, and it has a hollow seating the annular cavity of which is connected to a gas-supply pipe and has numerous small perforations opening to the face of the valve-seating. From the space ll a passage leads to a vertical pipe P, which is kept heated by a gas-burner, and which has a cap p, that can be screwed more or less down, so as to diminish or increase the interior capacity of the pipe I.

The action of the engine is as follows: As the piston C ascends, the valve G rises, admitting air mixed with gas into the space below the piston, the valve F at this time remaining closed. compresses the gaseous mixture, and when the pressure is sufficient a portion of the The piston then descending mixture forced into the heated pipe P becomes ignited. The ignition is communicated to the charge in the cylinder and the piston C is propelled upward. During the subsequent descent of the piston the exhaust-valve F is opened and the products of combustion are expelled. By adjusting the cap p of the heated pipe I), which after each ignition remains charged with products of combustion, the volume of the products contained in the pipe can be so regulated that their compression to the extent necessary to secure ignition of the cylinder-charge takes place just as the piston C reaches the'end of its compressingstroke, thus dispensing with valve-gear such as is usually employed to put the igniting apparatus in communication with the charge.

Obviously, instead of employing a cap p, screwing onto the exterior of the heated pipe l), a plunger might be screwed into its interior in order to regulate its capacity for the purpose above stated.

Having thus described the nature of my invention and the best means I know of carrying the same into practical elfecn, I claim- A gas-motor engine having a vertical cylinder made with brackets projecting up therefrom to carry the crank-shaft, and having in a hollow base under the cylinder a valve-box containing a self-acting air and gas supply valve and an exhaust-valve closed bya spring and opened at every alternate revolution of the crank-shaft by a lever worked by a crank eccentric or cam caused to revolve by gear at halt` the speed of the shaft, having also in communication with the cylinder-bottom an igniting-pipe heated by a burner, this pipe being adjustable in length, all substantially as described.

In testimony whereof I have signed my name to this specification, in thc presence of two subscribinwitnesses, this 3d day of May, A. D. i889.

J. J. PURNELL.

Witnesses:

OLIVER IMRAY, Patent Agent, 2S Southampton Bm'ldngs,

London, W. C'.

JN0. P. M. MILLARD, Clerk 'to lllfeszs'rs. Abel d' Imra'y, Consulting Engineers and Patent Agents, 28 Sonthampton Buildings, London., IV. C. 

